duncan



N0.v52,o48. v PATENTEDFEBgmlQM, 'LDUNGML ELECTRIC METER. 'APPLIQATION rLBD 00123, 1903.

N0 MODEL.

thc armature that all of the turns thereof are not initially included in circuit, the switcharm engaging an intermediate button 14, so that when the meter is put out to service a portion of lthe compensating winding maybe excluded from circuit to avoid creeping', or ad'- di i ional winding may be included in circuit to compensate for any increase in friction that arises. The switching device and the. connectionsl thereof with the compensating coil thus form a very effective means for varying the field, due to the compensating or torque coil. The switch-arm i6 connected with one main, a terminal of the torque-coil with the other main, and more or less of the torque-coil between the mains, according to the position of the switch-arm. The torque-coil is desirably wound in such a manner that a tap or branclr l5 maybe brought out every fifty or one hundred turns or any other number preferable. For example, when the switch-arm 16 is on the uppermost contact-button there may only be a few hundred turns of the coil in bridge of the mains, the number of turns included in bridge being increased as the switch-arm is moved downwardly. -As indicated, each compensating or torque coil is included in bridge of the mains, so as to be subject to the impressed pressure and so as to create a field that is constant in strength for a given position of the switch-arm and always present irrespective of the presence or absence of translating devices in the consumption-circuit. rl`he torque or compensating coil is suitably included in circuit in accordance with either arrangement shown. In Fig. l it is shown partially included and adapted for complete inclusion in series with the armature and commutator. In Fig.: 2 the armature and commutator are'in one bridge, while the torque-coil is shown partially included and adapted for complete inclusion in a bridge between the means that is distinct from the armature-bridge. In the arrangement shown in Fig. l obviously a single extraneous resistance 8 will be sucient for both the armature' and compensating coil. In the' arrangement shown in Fig. 2 additional vresistance 18 is desirable for the compensating coil.

There is a particularly advantageous result gained by means of-my invention that is not readily appa-rent without explanation. To those familiar with the art it is known that when a meter has been in service some time it not only usually runs too slow on light loads, but runs a little fast on high loads by reason of themagnets becoming weakened. I have found that by cutting' more turns of the compensating coil into circuit increased friction is not only compensated for to correct speed on small loads, but at the same timeit also may correct the increased speedon fuil load by virtue of the increase eifectedin the resistance in the armature-circuit. i prefer, however, to make the coii of as low resistance as possible in comparison with the resistance of the armature and resistance 8, though it would' be possible to make said coil of high resistance-wire and connect it directly across the mains. rlhe arrangement shown in Fig. 2

has the advantage of permitting the turns coil and may be disposed upon the exterior or interior thereof and'ldistributed toy both series field-coils, if desired.

Having thus described my invention,1 claim as new, and desire to secure by Letters Patent. the following:

1. The combination with a source of current, of mains leading therefrom to supply translating devices, a motor-meter having an armature and acurrent field-Winding, a friction compensating coil subject to the pressure of the circuit and provided to furnish a field for the armature anda switching device` having a number of contactbuttons connected with different portions of said coil and a switcharm adapted to engage said buttons and thereby render more `or less of said coil subjectto the pressure of the circuit, substantially as described. l

2. The combination with a source of current, of mains leading therefrom to supply translating devices, a motor-meter having a current field-Winding and a wound armature with its commutatorv and brushes, said armature IOO being subject to the pressure of the circuit, a y

friction compensating coil subject to the pressure of the circuit and provided'to furnisha field. for the armature and a switching device having a number of contact-buttons connected with different portions of said Vcoil and -a switch-arm adapted to engage said buttons and thereby render more or less of said coil subject to the pressure of the circuit, substantially as described.

3. The combination with a source of current, of mains leading therefrom to supply translating devices, a motor-meter having an arma- .ture and a current field-winding, a friction compensating coil subject to the pressure of lthe-circuit and provided to furnish a eld for the armature and switching mechanism for rendering more or less of said coil subject to the pressure of the circuit, substantially as described. Y

a. The combination with a source of current,

IZO

of mains leading tl erefrom to supply translating devices, -a motor-meter having a current field-Windmg and a wound armature w1th its commutator and brushes, said armature being subject to the pressure of the circuit, a friction compensating coil subject to the pressure of the circuit and provided to furnish a field for the armature and switching mechanism for rendering more'or less of said coii subject to the pressure of the circuit, substantially as described.

5. In c. meter, the combination with the motor element thereof, including armature and field portions, of a friction compensating coil for producing a field for the armature and a switching device havin g a number of contactbuttons connected with different portions of said coil and e switch-arm adapted to engage said buttons and thereby include more or less of said coil in circuit, substantially as described.

6. In n meter, the combination with the'motor element thereof, including field portions and e. wound armature with its commutator und brushes, yof a friction compensating coil for producirm,- a. field for the armature and a switching device having e number of contactbuttons connected with diiierent portions of said coii and a switch-arm adapted to engage said buttons and thereby include vmore or less of said coil in circuit, substantially as described.

7 In a. meter, the combination with the motor element thereof, including armature and field portions, of a friction compensatingcoil for producing n. field for the armature, and switching mechanism for inciuding more or less of said coil in circuit, substantially as dei scribed.

switching mechanism for including more -or less of sind coil in circuit, substantially as described.

9. .in a. meter, the combination with the motor element thereof, including armature and eld portions, of a friction compensating coil adapted to be located between the mains of the system containing the meter for produc ing 'a field for the armature end a switching device having a number of contact-buttons connected with different portions of said coil, and a switch-erm adapted to engage said buttons end thereby include more or less of said coil in circuit, substantially' as described.

iO. In a meter, the combination with the motor element thereof, including field portions and 'a wound armature with its commutator and brushes, of a friction compensating coil adapted to be located between the mains of the system containing the meter for producing a. lield for the armature and a switching device having a number of contact-buttons connected with dierent portions of said coil, and s switch-arm adapted to engage said buttons and thereby include more or less of said coil in circuit, substantially as described.

11. In a meter, the combination with the i motor element thereof, including armature and eld portions, of a friction compensating coil adapted to be located between the meins of the system containing the meter for producing a iiold for the armature, and switching mechanism for including more or less of seid coil in circuit, substantially as described.

l2. In a meter, the combination with the motor element thereof, including field portions and a Wound armature with its commutetor and brushes, of a friction compensating coil adapted to be locatedbetween the meins of the system containing the meter for pro-L ducing e field for the armature, and switching mechanism for including more or less ofsaid coil in circuit, substantially as described.

In witness whereof I hereunto subscribe my neme this 23d day of September, A. D. 1903.

THQMAS DUNCAN.

Witnesses: y

CHARLES J'oNns, BLANCHE A. MILLER. 

